The present disclosure relates to a process for creating prototype parts, and particularly, to a process for creating rapid prototype parts using stereolithography, selective laser sintering (SLS), or casting techniques. More particularly, the present disclosure relates to a process for changing or enhancing the characteristics of prototypes made by stereolithography, SLS, or casting techniques.
Manufacturers who develop new products oftentimes have prototype parts of the new products made for evaluation purposes. In addition, prototype parts sometimes are used to create casts which, in turn, are used to create production parts. Processes for making rapid prototype parts include stereolithography, selective laser sintering (SLS), and casting non-metallic materials, such as resins. In stereolithography, laser energy is used to cure selected areas of successive cross sections of a liquid, photopolymer resin that is introduced into a container. The areas that are laser cured are based on cross sections of the prototype that are generated by a CAD system. The photopolymer solidifies in the specific areas exposed to the laser beam. Thus, the prototype is created layer-by-layer as the liquid resin is fed into the container. Using stereolithography, the transition from CAD data to a three-dimensional prototype is accomplished relatively quickly, sometimes in just a few hours. In SLS, successive layers of powdered materials are sintered or fused together in an environmentally controlled chamber by exposure to a carbon dioxide laser. Thermoplastics, investment casting wax, polycarbonate, and nylon are a few of the types of powdered materials that are used in SLS for the creation of three-dimensional prototypes. In prototype casting, a prototype part is made by pouring and/or vacuuming a resinous material into a mold.
While conventional stereolithography, SLS, and casting techniques are able to produce, in a relatively short period of time, three dimensional prototype parts having fairly complicated shapes, the parts produced by these techniques heretofore have been relatively brittle. As a result, prototype parts made in accordance with conventional rapid prototype production techniques are not very durable and are susceptible to breaking due to temperature changes, inadvertent impacts, routine handling, and the like.